DE1247625B - Use of organic silicon compounds as additives to organic binders to bind inorganic compounds based on silicon - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C08k

German class: 39 b -22/01

Number: 1247 625

File number: A 31835 IV c / 39 b

Filing date: April 16, 1959

Opened on: August 17, 1967

Condensation resins of the phenol-formaldehyde and amino resin types have been around for a long time as a binder in technical use, both in the form of aqueous solutions and in liquid form or dissolved in organic agents. Such resins are also in the form of binders as binders Powders and suspensions have been used.

For many purposes these binders show insufficient binding properties. This is especially true then the case when the bonds created are exposed to moisture and especially when they serve to bind silicon-containing substances that are released during storage or use Exposure to moisture.

The invention relates to an improvement of this type of binder or its properties with regard to The above said, in particular, the strength of the body should be increased when it is under the influence of Exposed to moisture.

This object is achieved according to the invention through the use of an organic silicon compound the general formula

R "six ₄ _"

where R is an organic radical containing a reactive hydroxyl, amino or aldehyde group, X is an alkoxy group, a hydroxyl group or a halogen atom and η is a number 1, 2 or 3, in an amount of 0.05 to 5% , based on the dry weight of the final mass, as an additive to binders made from phenol-formaldehyde and furan resins and products that form aminoplasts with formaldehyde. The admixed substance contains on the one hand one or more groups which react with the silicon atoms of the substance to be bound and on the other hand one or more groups which form condensation products with the resin used. The organic silicon compound is added to the binder.

It has been shown that even very small amounts of the organic silicon compound to be used of 0.05% exert a beneficial effect and that no further advantages are obtained if the amount exceeds 5%. For many purposes, the cheapest addition amount of this is the binder modifying intermediate mass at 0.1 to 0.5%, based on the dry weight of the Biridem mass.

Examples of commonly used resins in which the organic silicon compounds can be used as modifying agents are phenol and alkylphenol-formaldehyde resins and furan resins. Organic silicon compounds are used as examples of the amino resins
as an additive to organic binders for binding
inorganic masses based on silicon

Applicant:

AB Höganäsmetoder, Häganäs (Sweden)

Representative:

Dr.-Ing. Hj. V. Blacks, patent attorney,

Munich 5, Müllers tr. 31

Named as inventor:

Borge Ingmar Carlström, beach bathing;

Karl-Axel Rumberg, Viken (Sweden)

Claimed priority:

Sweden April 25, 1958 (4045)

can not only use urea and thiourea resins, but also plastic materials on melamine and Be called casein base.

Examples of organic silicon compounds to be used are: γ-aminopropyl-triethoxysilane, δ, δ- diaminobutyl- β- aminoethyl-dimethoxysilane, p-aminophenyltriphenoxysilane, p-oxyphenyl-diethoxysilane and p-aminophenylmethyltriethoxysilane.

The binder can be used in a wide variety of ways by the organic silicon compound to be used, which, among other things, depends on the resin base. Although the to be used Organic silicon compounds as such are not water-soluble, they can be aqueous Solution of a water-soluble resin are added because immediately a reaction between the reactive group or groups of the water-soluble resin and the organic silicon compound occurs, whereby the latter is converted into a water-soluble form. Is the Binder in the form of a powder, the modifying agent can be added to a melt, whereupon the mixture is ground to a powder after it has solidified.

As far as the inventive level of the subject matter of the invention is concerned, it should be noted that as a binder Many organic silicon compounds would be conceivable for substances containing silicon. According to the invention to be used silicon compounds are the

709 637/727

the usual extraordinarily superior. It was by no means obvious and was by no means to be expected that precisely these silicon compounds would be cheaper than other compounds of these Art.

In the following, the effect of conventional binders and binders that using the organic silicon compound prepared by comparative Determination of the flexural or compressive strength of correspondingly produced bodies is shown.

example 1
Binding of glass threads

The glass threads were made from one in a platinum vessel with the lower outlet located molten glass drawn by means of a rapidly rotating drum. The temperature of the melt and the speed of the drum were adjusted so that a thread of 7 μ diameter was obtained. The thread is pulled for a period of 5 minutes, and the binder is fed in on the way to the drum. The thread bundle is cut free from the drum and more binder is added. That The bundle is then dried at room temperature, whereupon the binder with the bundle hanging down is cured at elevated temperatures. From the thus obtained tied thread bundle in in the form of 9 cm long rods, small rods intended to serve as test samples are cut off. Ten rods were immediately examined for flexural strength in an apparatus with a distance of 50 mm between the support edges. The maximum weight that. that withstand rods here is a measure of the adhesion, because the flexibility does not depend on the breakage of the threads, but from loosening or tearing the bond between the threads. Ten other chopsticks were 1 week exposed to moisture-saturated air at room temperature for a long time and then. subjected to the bending test, in order to determine the influence of moisture on the bond. '",.,

The tests were carried out on rods made from boron-containing glass threads with a, binder content of 6%, part with conventional 'phenol-formaldehyde resin and part with the same, however, modified using 0.4% γ-aminopnropyltriethoxysilane Resin were bound. The following values were obtained: '. . ;

Common phenol Modified aldehyde resin resin Breaking load in dry in a state ... 420 g 580 g Breaking load after moist storage 200 g 560 g Preserved strength 48% 97%

nolform aldehyde resin of the novolak type mixed with an addition of 10% hexamethylenetetramine and Cured for 20 minutes at 160 ° C. Another sample of the same olive stone was found to be 15% the same resin composition added, but using 0.5% γ-aminopropyltriethoxysilane The product was made in the shape of cylinders with a height of 30 mm and a diameter of 20 mm cured for 20 minutes at 160 ° C. The samples were Immersed in water at 80 ° C for 2 hours. The compressive strength test showed

for the rehearsals

without the use of silane .... 84 kg / cm ²

for the rehearsals

with the use of silane .... 110 kg / cm ²

This means a 31% improvement in compressive strength.

Example 3

Part of a silicon carbide powder with a sieve analysis of 70 to 280 meshes was found to be 10% Phenol-formaldehyde resin of the resol type in the form of a 75% strength aqueous solution without the addition of any Modifier mixed and another part of the powder with the simultaneous addition of 0.2% γ-ammopropyltriethoxysilane. From both mixtures test pieces were made in the form of cylinders 3 cm high and 2.3 cm in diameter, the 30 minutes at 80 ° C and. then cured at 160 ° C for 30 minutes. To after cooling, the bodies were immersed in water at 80 ° C. for 4 hours and then the pressure test subject. This gave compressive strengths

for the rehearsals

without the use of silane .... 164 kg / cm ²

for the rehearsals

with the use of silane 305 kg / cm ²

This means an improvement in compressive strength of 86%.

Example4

'. According to. , .Example 1 rods were made from a boron-free glass.

The binding was carried out in the same way as described there, but as a binder Urea resin used, once without modifying agent and once mixed with 0.3% y-aminopropyltriethoxysilane, based on the dry weight of the resin. The strength was in the bending machine found when the load at which the specimens were broken. Partly the samples were taken immediately after Completion and partly after one week of storage in moisture-saturated air at room temperature examined. The following values resulted:

B e i s ρ i e 1 2

An olivine stone with a particle size accordingly a 20 mesh size and 80% below 80 mesh size was 15% Phe-

60 Breaking load resin without with ₆ when dry, g additive additive Breaking load after moist storage, g .. 482 598 Strength retained,% 33 209 7th 35

Claims (1)

Claim: Use of an organic silicon compound of the general formula where R is an organic radical containing a reactive hydroxyl, amino or aldehyde group, X is an alkoxy group, a hydroxyl group or a halogen atom and η is a number 1, 2 or 3, in an amount of 0.05 to 5% , based on the dry weight of the final mass, as an additive to binders made from phenol-formaldehyde and furan resins as well as substances that form aminoplasts with formaldehyde to bind inorganic silicon-containing substances. Considered publications:
German patent specification No. 698 389. 709 637/727 8.67